How to Convert Between Binary, Hex, Octal & Decimal

Programmers live between number systems — decimal for humans, binary for hardware, hex for colours and memory addresses, octal for file permissions. Converting between them in your head is error-prone, and a wrong digit can mean a wrong colour or a broken bitmask. A base converter does it instantly and correctly.

The bases you'll meet

When you need to convert

• Colours — turn a hex colour into RGB decimal values, or back.
• Bit manipulation — read a binary flag as decimal or hex.
• Permissions — translate rwxr-xr-x to octal 755.
• Debugging — make sense of hex dumps and memory addresses.

Step-by-step: convert with ToolsGravity

1. Open the Number Base Converter.
2. Enter a value in any base — binary, octal, decimal, or hex.
3. Read the equivalent in all the other bases at once, and copy the one you need.

The same number, four ways

Tips

• Watch the prefixes. Code often marks bases: 0b for binary, 0o for octal, 0x for hex.
• Hex and binary line up neatly. Each hex digit is exactly four binary digits, which is why hex is used as shorthand for binary.
• Working with colours? For hex ↔ RGB ↔ HSL specifically, a dedicated colour converter is easier than raw base conversion.

Summary

Binary, octal, decimal, and hex are just different ways of writing the same number — and converting between them by hand invites mistakes. Enter a value once and read every base at a glance with the ToolsGravity Number Base Converter, right in your browser.